Quadrature Sub-Harmonic mixing to DC or low-IF can be attractive for signal processing at Ka-band. Frequency translation is performed without the need for a local oscillator at the received signal frequency. A lower frequency reference takes advantage of the higher quality of tuning elements and avoids high frequency, powerhungry dividers in the synthesizer. Moreover DC offsetand second-order inter-modulation distortion, due to poor LO-RF isolation, are mitigated by the LO running at lower frequency. This paper presents the receiver IC architecture and experiments from a quadrature demodulator realized in 65nm CMOS.
A CMOS Sub-Harmonic Architecture for Signal Down-Converion at Ka-Band / F., Svelto; Mazzanti, Andrea; M., Sosio; M., Repossi. - STAMPA. - (2007), pp. 179-182. ((Intervento presentato al convegno IEEE International Workshop on Radio-Frequency Integration Technology, RFIT 2007 tenutosi a Singapore nel Dicembre 2007 [10.1109/RFIT.2007.4443945].